In Lucene 8 searches can skip non-competitive hits if the total hit count is not requested.
It is also possible to track the number of hits up to a certain threshold. This is a trade off to speed up searches while still being able to know a lower bound of the total hit count. This change adds the ability to set this threshold directly in the track_total_hits search option. A boolean value (true, false) indicates whether the total hit count should be tracked in the response. When set as an integer this option allows to compute a lower bound of the total hits while preserving the ability to skip non-competitive hits when enough matches have been collected.
Relates #33028
This commit changes the format of the `hits.total` in the search response to be an object with
a `value` and a `relation`. The `value` indicates the number of hits that match the query and the
`relation` indicates whether the number is accurate (in which case the relation is equals to `eq`)
or a lower bound of the total (in which case it is equals to `gte`).
This change also adds a parameter called `rest_total_hits_as_int` that can be used in the
search APIs to opt out from this change (retrieve the total hits as a number in the rest response).
Note that currently all search responses are accurate (`track_total_hits: true`) or they don't contain
`hits.total` (`track_total_hits: true`). We'll add a way to get a lower bound of the total hits in a
follow up (to allow numbers to be passed to `track_total_hits`).
Relates #33028
This change adds a soft limit to open scroll contexts that can be controlled with the dynamic cluster setting `search.max_open_scroll_context` (defaults to 500).
The documentation of `search_after` recommends to use the `_id`
field as a tiebreaker for the sort without warning against
the additional memory required. This change changes the recommandation
to use a copy of the `_id` field with doc_values enabled.
The main benefit of the upgrade for users is the search optimization for top scored documents when the total hit count is not needed. However this optimization is not activated in this change, there is another issue opened to discuss how it should be integrated smoothly.
Some comments about the change:
* Tests that can produce negative scores have been adapted but we need to forbid them completely: #33309Closes#32899
* Search: Support of wildcard on docvalue_fields
For consistency with stored_fields, docvalue_fields should support the use of wildcards.
Documentation of doc values fields is updated accordingly.
See also: #26390Closes#26299
Today it is unclear what guarantees are offered by the search preference
feature, and we claim a guarantee that is stronger than what we really offer:
> A custom value will be used to guarantee that the same shards will be used
> for the same custom value.
This commit clarifies this documentation.
Forward-port of #32098 to `master`.
Adds support for `ignore_unmapped` parameter in geo distance sorting,
which is functionally equivalent to specifying an `unmapped_type` in
the field sort.
Closes#28152
This commit adds the ability to configure how a docvalue field should be
formatted, so that it would be possible eg. to return a date field
formatted as the number of milliseconds since Epoch.
Closes#27740
Currently the first snippet in the documentation test in script-fields.asciidoc
isn't executed, although it has the CONSOLE annotation. Adding a test setup
annotation to it seems to fix the problem.
* Clarify documentation of scroll_id
The Scroll API may return the same scroll ID for multiple requests due to server side state. This is not clear from the current documentation.
* Further clarify scroll ID return behaviour
Some features have been deprecated since `6.0` like the `_parent` field or the
ability to have multiple types per index. This allows to remove quite some
code, which in-turn will hopefully make it easier to proceed with the removal
of types.
Increase the default limit of `index.highlight.max_analyzed_offset` to 1M instead of previous 10K.
Enhance an error message when offset increased to include field name, index name and doc_id.
Relates to https://github.com/elastic/kibana/issues/16764
* Limit the analyzed text for highlighting
- Introduce index level settings to control the max number of character
to be analyzed for highlighting
- Throw an error if analysis is required on a larger text
Closes#27517
Allowing `_doc` as a type will enable users to make the transition to 7.0
smoother since the index APIs will be `PUT index/_doc/id` and `POST index/_doc`.
This also moves most of the documentation to `_doc` as a type name.
Closes#27750Closes#27751
Also include _type and _id for parent/child hits inside inner hits.
In the case of top_hits aggregation the nested search hits are
directly returned and are not grouped by a root or parent document, so
it is important to include the _id and _index attributes in order to know
to what documents these nested search hits belong to.
Closes#27053
Due to a change happened via #26102 to make the nested source consistent
with or without source filtering, the _source of a nested inner hit was
always wrapped in the parent path. This turned out to be not ideal for
users relying on the nested source, as it would require additional parsing
on the client side. This change fixes this, the _source of nested inner hits
is now no longer wrapped by parent json objects, irregardless of whether
the _source is included as is or source filtering is used.
Internally source filtering and highlighting relies on the fact that the
_source of nested inner hits are accessible by its full field path, so
in order to now break this, the conversion of the _source into its binary
form is performed in FetchSourceSubPhase, after any potential source filtering
is performed to make sure the structure of _source of the nested inner hit
is consistent irregardless if source filtering is performed.
PR for #26944Closes#26944
The shard preference _primary, _replica and its variants were useful
for the asynchronous replication. However, with the current impl, they
are no longer useful and should be removed.
Closes#26335
* Fix percolator highlight sub fetch phase to not highlight query twice
The PercolatorHighlightSubFetchPhase does not override hitExecute and since it extends HighlightPhase the search hits
are highlighted twice (by the highlight phase and then by the percolator). This does not alter the results, the second highlighting
just overrides the first one but this slow down the request because it duplicates the work.
Multi-level Nested Sort with Filters
Allow multiple levels of nested sorting where each level can have it's own filter.
Backward compatible with previous single-level nested sort.
* Remove the _all metadata field
This change removes the `_all` metadata field. This field is deprecated in 6
and cannot be activated for indices created in 6 so it can be safely removed in
the next major version (e.g. 7).
